According to a new study in the journal Human Reproduction, researchers have found that long-term stress may reduce a woman’s ability to get pregnant by as much as 29 percent.

From 2005 to 2009, researchers studied 501 American couples, aged 18 to 40 years old, for up to a year as they tried to conceive or until they became pregnant. The women didn’t have any known fertility problems and they had just started trying to conceive.

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Saliva samples were collected from women enrolled in the study the morning following enrollment and then the morning following their first study-observed menstrual cycle. Specimens were measured for the presence of cortisol and alpha-amylase, which are two biomarkers of stress. TTP was measured in cycles.

High Levels of Stress Reduce Ability to Get Pregnant

The researchers found that women with high levels of alpha-amylase are 29 percent less likely to get pregnant each month and are more than twice as likely to meet the clinical definition of infertility (remaining not pregnant despite 12 months of regular unprotected intercourse), compared with women who had low levels of this protein enzyme.

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Among the 401 (80 percent) women who completed the protocol, 347 (87 percent) became pregnant and 54 (13 percent) did not become pregnant.

Courtney Denning-Johnson Lynch, director of reproductive epidemiology at The Ohio State University Wexner Medical Center and the principal investigator of the LIFE Study’s psychological stress protocol, said a statement, “This is now the second study in which we have demonstrated that women with high levels of the stress biomarker salivary alpha-amylase have a lower probability of becoming pregnant, compared to women with low levels of this biomarker. For the first time, we’ve shown that this effect is potentially clinically meaningful, as it’s associated with a greater than two-fold increased risk of infertility among these women.”

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Managing Stress Is Crucial

Lynch said the findings should encourage women who are experiencing difficulty getting pregnant to consider managing their stress using stress-reduction techniques such as yoga, meditation, and mindfulness. Advising that couples should not blame themselves if they are having fertility problems, Lynch said that stress is not the only or most important factor involved in a woman’s ability to get pregnant.

Emphasizing that getting rid of stressors might shorten the time couples need to become pregnant versus ignoring stress, Germaine Buck Louis, the LIFE Study’s principal investigator, said women will likely know which stress reduction strategy suits them best, since “a one-size-fits-all stress-reduction solution isn’t likely.”

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